In the early to mid-2000s, stretchable wristbands became popular. Such wristbands were generally made of silicone and are sometimes called “awareness bracelets” to distinguish them from other types of wristbands. Aside from their pervasive appeal as fashion accessories, stretchable wristbands have several other uses. Perhaps their most well-known use is in fundraising for charitable causes. Stretchable wristbands have been used in campaigns against terminal diseases (e.g. LiveStrong, American Cancer Society), in support of victims of natural disasters (e.g. Tsunami Relief Wristbands), to show solidarity with sports teams or community groups, as well as for a wide variety of other uses.
Much of the stretchable wristband's popularity stems from its capacity to convey a message. A wristband's look and feel can be customized to fit the desires of the promoters, particularly through color selection and pattern design. Most manufacturers provide a wide range of color choices for stretchable wristbands and alter the color by dying the pre-molded silicone stock. In addition to single color bands, manufacturers are able to provide multi-colored segmented bands and marbleized or “swirled” bands that combine several colors in an intertwined pattern.
Beyond simply altering the color and design, a message can be added to the wristband by one or more of the following means: embossing (raised letters that protrude about 2 millimeters from the band's surface); debossing (letters that are recessed into the band); colored debossing (adding dye or other coloring to debossed letters); and screen printing (silk screening text directly to the band's surface).
Although many bracelets are produced with other synthetic rubber materials, the majority of current decorative wristbands are made specifically from silicone. Silicone is a bonded polymer substance with numerous elastomeric qualities that make it both flexible and water resistant. Silicone is also fairly heat resistant but can be susceptible to deterioration from UV exposure.
Silicone rubber stock is typically extruded into strips or tubes of varying thickness, which are then compression molded into the familiar round cross-section of a wristband. The silicone bands display high levels of elasticity, allowing them to be pulled or drawn over most wrists. As a result, the majority of these decorative wristbands are produced with a circumference between about 18 and 22 cm. The width of the wristband is usually between about 12 mm and 14 mm, while the thickness is approximately 4 to 5 mm.
In a separate development, financial service providers began introducing contactless radio frequency identification (RFID) credit cards around 2004 or 2005. These cards can be waved at a retailer's reader, eliminating the need for a “swipe” or signature. Leading banks are now issuing millions of contactless credit and debit cards to consumers, and leading retailers are installing contactless readers that are integrated with point-of-sale (POS) systems. The rate of adoption of contactless payment systems is one of the highest ever observed for emerging payments products in recent years and signals a unique market opportunity.
RFID devices, such as credit cards, debit cards, key fobs, documents, watches, cell phone covers and the like, consist of a secure microcontroller or equivalent intelligence, internal memory, and a small antenna embedded in a device that communicates with a reader through a contactless radio frequency interface. The microchip in an RFID device can securely manage, store, and provide access to data on the device in which they are embedded. They can perform internal functions (e.g., encryption) and interact intelligently with the contactless reader. This technology is distinguishable from passive radio frequency chip technologies, such as the RFID tags used for inventory management/product tracking applications, which require minimal functionality.
A contactless payment requires no physical connection between the consumer payment device and the physical point of sale terminal. There are a number of providers of contactless payment systems in the United States, including American Express (ExpressPay), MasterCard (PayPass), and Visa (PayWave). Each of these products is based on the ISO/IEC 14443 standard, the international standard for contactless smart chip technology. Under this standard, contactless payment devices are restricted to be read within 2 to 4 cm of a point of sale terminals opposed to RFID tags which are designed to be read at large distances. In addition, contactless payment applications include other measures that are specifically designed to protect the security of the consumer's information and the payment transaction.
By issuing secure contactless payment devices, financial service providers are not only supplying consumers with a more convenient payment mechanism, they are also increasing transaction volumes by replacing cash. In addition, service providers can now differentiate themselves with innovative new form factors.
It is now apparent that it would be desirable to combine the ubiquity of the stretchable wristband with the convenience of RFID technology for use in contactless payment systems, healthcare systems, and other systems. In a contactless payment system, such a method and system would allow faster and easier payment transactions and would allow the user to maintain control of the RFID device at all times, both during the transaction and between transactions. In addition, it would allow payments to be processed through the same, reliable payment network as current contactless payment systems and magnetic strip transactions. However, the existing technology is not well suited for combining a stretchable wristband with an RFID device.
For example, existing wristbands with RFID chips are not well suited for use in a contactless payment system. The commercially available wristbands comply with the ISO 15693 air protocol, an unencrypted protocol designed primarily for inventory tracking, using both high frequency (13.56 MHz) and ultra-high frequency (860-960 MHz) bands. A representative example of a commercially available wristband is shown in FIG. 1. In this wristband 100, the RFID component is contained in the large area 102 adjacent to the snap 101. These wristbands are generally design for short term (1-2 days continuous) use. NXP I-code SLI and Texas Instruments Tag-It 2K are examples of chips commonly used in these wristbands. The wristbands are generally constructed of vinyl or polyester laminated films. These wristbands are not stretchable and are not configured for use with contactless payment systems.
The commercially available chips that are designed for use in a contactless payment system are sold in a molded package, similar, if not identical, to the NOA3 package offered by Nedcard Ltd. of Belgium. A representative package size is 5.15 mm×8.0 mm×0325 mm. The chip size is typically 2 mm×2 mm×0.015 mm though there is significant variation between manufacturers. Because, the package is designed to protect the IC during fabrication and are designed for use on a PVC laminated card, the package is stiff and very robust and, as a result, not suitable for use in a stretchable wristband.
As is apparent to those skilled in the art, there are numerous obstacles to embedding traditional RFID microchips and antennas into a stretchable wristband. For example, the wristband must possess the requisite elasticity to stretch when drawn over the user's hand, but must also be UV stable enough to protect the RFID chip and antenna. The wristband must be durable enough to withstand the rigors of daily living, including activities such as exercise and bathing, while protecting the integrity of the chip. To maximize market acceptance, the wristband must be configured dimensionally to conform to currently available wristbands which may require the microchip and antenna to be smaller than otherwise permissible. The microchip and antenna must be configured on or in the wristband in such a manner that the stretching of the band during use does not damage the microchip, the antenna, or the connection therebetween.
Other issues related to the combination of elastic wristbands and RFID devices arise in the manufacturing process. The microchip and antenna must be protected during the manufacturing process so that they are not damaged or destroyed and the connection between the microchip and antenna must not be dislodged or compromised. The microchip and antenna package must be properly adhered to the wristband, either temporarily during the molding process if the package is included within the mold, or permanently if the package is adhered to the outside of the wristband. Resins must be selected which match the “skin feel” of currently available wristbands but that are also compatible with the microchip and antenna. In addition, the finished product must be aesthetically pleasing and appear the same as commercially available wristbands, including matching the color, indented lettering and, if the wristband is manufactured in two parts, making the two portions of the wristband indistinguishable.
In addition to the complexities inherent in the use and manufacture of an RFID wristband, issues arise with the integration into the existing contactless payment system. The RFID device must be selected so that, when it is installed in or on the wristband, the wristband complies with ISO/IEC 14443, the international standard for contactless smart chip technology. Since the wristband must be relatively soft for the wristband to be sufficiently flexible, the components embedded in this material are not well protected against external pressure and are liable to become damaged quickly when the wristband is worn on the wrist. This is likely one reason that this type of wristband has not met with commercial success to date.
For the forgoing reasons, it is desirable to have a stretchable wristband with an embedded RFID chip and antenna which is capable of continuous wear over extended periods and also compatible with ISO/TEC 14443 standards and existing point of sale payment systems.